Aspartate aminotransferase (GOT) catalyzes the transfer of the amino group from aspartate to oxoglutarate with the formation of glutamate and oxalacetate.
L-Aspartate + 2-Oxoglutarate L-Glutamate + Oxalacetate
Alanine aminotransferase (GPT) catalyzes the transfer of the amino group from alanine to oxoglutarate with the formation of glutamate and pyruvate.
L-Alanine + 2-Oxoglutarate Glutamate + Pyruvate
The transaminase activity is proportional to the amount of oxalacetate or pyruvate formed over a definite period of time and is measured by the reaction with 2,4-dinitrophenylhydrazine (DNPH) and measurement of the color formed in an alkaline solution.